I JUST bought one, Like today.So far I REALLY like it, It is VERY quiet and just the right size. I checked my petsmart and they had all the replacements for it. I don't know if the walmart would but I know Petsmart did.

Since I just bought it I cant give that much help but my betta is enjoying it so far. But I can tell you if I run into any problems :). Hope i helped

I also have this tank. Walmart and Petsmart carry the filter cartridges. I don't have a problem cleaning mine. I do 100% changes once or twice a week. Here is a picture so that you can see the size compared to a betta.

I have those tanks and I love them! They scratch easily though, so make sure that you clean them with something soft. I get my replaceable lights at Walmart. They sell 2 for $2. I'm sure Petsmart or Petco have them, but I get mine at Walmart.

This is what I'm looking to get for Blue Jeans who is still in a 1 gal.. but I can never find them at wal-mart.. at petsmart and pet supermarket they are TWICE as much :( as far as I know they are the only 2.5 gallon kits on the market at least within a normal price.